private void CreateInitialGraph()
{
var ptg = new PointsToGraph();
var variables = cfg.GetVariables();
foreach (var variable in variables)
{
if (variable.Type.IsValueType)
{
continue;
}
if (variable.IsParameter)
{
var isThisParameter = variable.Name == "this";
var kind = isThisParameter ? PTGNodeKind.Object : PTGNodeKind.Unknown;
var node = new PTGNode(nextPTGNodeId++, variable.Type, 0, kind);
ptg.Add(node);
ptg.PointsTo(variable, node);
}
else
{
ptg.Add(variable);
}
}
this.initialGraph = ptg;
}
public PointsToGraph()
{
this.Null = new PTGNode(0, PTGNodeKind.Null);
this.variables = new MapSet <IVariable, PTGNode>();
this.nodes = new Dictionary <int, PTGNode>();
this.Add(this.Null);
}
public void Union(PointsToGraph ptg)
{
// add all new nodes
foreach (var node in ptg.Nodes)
{
if (this.Contains(node))
{
continue;
}
var clone = new PTGNode(node.Id, node.Type, node.Offset, node.Kind);
nodes.Add(clone.Id, clone);
}
// add all variables
foreach (var variable in ptg.Variables)
{
this.variables.Add(variable);
}
// add all edges
foreach (var node in ptg.Nodes)
{
var clone = nodes[node.Id];
// add variable <---> node edges
foreach (var variable in node.Variables)
{
clone.Variables.Add(variable);
this.variables.Add(variable, clone);
}
// add source -field-> node edges
foreach (var entry in node.Sources)
{
foreach (var source in entry.Value)
{
var source_clone = nodes[source.Id];
clone.Sources.Add(entry.Key, source_clone);
}
}
// add node -field-> target edges
foreach (var entry in node.Targets)
{
foreach (var target in entry.Value)
{
var target_clone = nodes[target.Id];
clone.Targets.Add(entry.Key, target_clone);
}
}
}
}
public bool SameEdges(PTGNode node)
{
if (node == null)
{
throw new ArgumentNullException("node");
}
return(this.Variables.SetEquals(node.Variables) &&
this.Sources.MapEquals(node.Sources) &&
this.Targets.MapEquals(node.Targets));
}
public void PointsTo(IVariable variable, PTGNode target)
{
#if DEBUG
if (!this.Contains(target))
{
throw new ArgumentException("Target node does not belong to this Points-to graph.", "target");
}
#endif
target.Variables.Add(variable);
this.variables.Add(variable, target);
}
public void PointsTo(PTGNode source, IFieldReference field, PTGNode target)
{
#if DEBUG
if (!this.Contains(source))
{
throw new ArgumentException("Source node does not belong to this Points-to graph.", "source");
}
if (!this.Contains(target))
{
throw new ArgumentException("Target node does not belong to this Points-to graph.", "target");
}
#endif
source.Targets.Add(field, target);
target.Sources.Add(field, source);
}
private PTGNode GetNode(PointsToGraph ptg, uint offset, ITypeReference type, PTGNodeKind kind = PTGNodeKind.Object)
{
PTGNode node;
if (nodeIdAtOffset.ContainsKey(offset))
{
var nodeId = nodeIdAtOffset[offset];
node = ptg.GetNode(nodeId);
}
else
{
var nodeId = nextPTGNodeId++;
node = new PTGNode(nodeId, type, offset, kind);
ptg.Add(node);
nodeIdAtOffset.Add(offset, nodeId);
}
return(node);
}
public void Add(PTGNode node)
{
nodes.Add(node.Id, node);
}
public bool Contains(PTGNode node)
{
return(this.ContainsNode(node.Id));
}